Biochemistry
6th Edition
ISBN: 9781305577206
Author: Reginald H. Garrett, Charles M. Grisham
Publisher: Cengage Learning
expand_more
expand_more
format_list_bulleted
Question
Chapter 21, Problem 2P
Interpretation Introduction
To calculate:
Introduction:
PSII is a complex protein which helps in electron transfer to plastoquinone from water using the light energy for driving. This produces oxygen and reduces the plastoquinone release into the membrane of photosynthesis.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
In cyclic photophosphorylation, it is estimated that two electrons must bepassed through the cycle to pump enough protons to generate one ATP.Assuming that the ∆G for hydrolysis of ATP under conditions existing inthe chloroplast is about -50 kJ/mol, what is the corresponding percent efficiency of cyclic photophosphorylation, using light of 700 nm?
What is midpoint potential of redox active centers in photosynthetic organisms? What factors affect this?
Also how does charge become offset during water oxidation rxns?.
When running cycle photophosphorylation and passaging electrons from PSI to two fully reduced PQH2s, how many photons would be necessary for the electrons to complete one cycle?
Chapter 21 Solutions
Biochemistry
Ch. 21 - P700* Has the Most Negative Standard Reduction...Ch. 21 - Prob. 2PCh. 21 - Prob. 3PCh. 21 - Prob. 4PCh. 21 - The Relative Efficiency of ATP Synthesis in...Ch. 21 - pH and in the Chloroplast Proton-Motive Force...Ch. 21 - Prob. 7PCh. 21 - Prob. 8PCh. 21 - Prob. 9PCh. 21 - Prob. 10P
Ch. 21 - Tracing the Fate of CO2 During Photosynthesis...Ch. 21 - Prob. 12PCh. 21 - Prob. 13PCh. 21 - The Source of the Oxygen Atoms in Photosynthetic...Ch. 21 - Prob. 15PCh. 21 - Prob. 16PCh. 21 - Prob. 17PCh. 21 - The Overall Free Energy Change for Photosynthetic...Ch. 21 - Prob. 19PCh. 21 - Prob. 20PCh. 21 - Prob. 21P
Knowledge Booster
Similar questions
- P700* Has the Most Negative Standard Reduction Potential Found in Nature In photosystem I. P700 in its ground state has an = +04 V. Excitation of P700 by a photon of 700-nm light alters The of P700* to -0.6 V. What is the efficiency of energy capture in this light reaction of P700?arrow_forwardThe Overall Free Energy Change for Photosynthetic NADP+ Reduction What is the overall free energy change (G) for noncyclic photosynthetic electron transport? 4 (700-nm photons) + 4 (680-nm photons) + 2 H2O + 2 NADP+O2 + 2 NADPH + 2H+arrow_forwardThe Relative Efficiency of ATP Synthesis in Noncyclic versus Cyclic Photophosphorylation If noncyclic photosynthetic electron transport leads to the translocation of 7 H+/2e- and cyclic photosynthetic electron transport leads to the translocation of 2 H+/e-, what is the relative photosynthetic efficiency of ATP synthesis (expressed as the number of photons absorbed per ATP synthesized) for noncyclic versus cyclic photophosphorylation? (Assume that the CF1CF0-ATP synthase yields 3 ATP/14 H+.)arrow_forward
- Melvin Calvin and Andrew Benson determined the steps in the light-independent reactions of photosynthesis by exposing the green alga Chlorella to CO2 labeled with the radioisotope carbon 14. By looking at which compounds the C14 ended up in, they were able to identify all intermediates in this cyclic pathway. Why did they predict correctly that the same set of intermediates would be formed in the light reaction in land plants?arrow_forwardIn cyclic photophosphorylation, it is estimated that two electrons must be passed through the cycle to pump enough protons to generate one ATP. Assuming that the ΔG for hydrolysis of ATP under conditions existing in the chloroplast is about -50 kJ/mol, what is the corresponding percent efficiency of cyclic photophosphorylation, using light of 700 nm?arrow_forwardIs it reasonable to list standard reduction potentials (see Chapter 20) for the reactions of photosynthesis? Why or why not?arrow_forward
- A substantial amount of energy is put into the photosynthetic electron transport to extract electronsf from water and to elevate the energy level of ferredoxin to a very strong reductant. The amount of energy in one NADPH is 218 kJ.mol-1. What is the percentage of this energy conserved in NADPH for the production of one mole of oxygen? What happened to the rest of the energy?arrow_forwardWhat is implied about the energyrequirements of photosystems I and II by the fact that there is a difference in the minimum wavelength of light needed for them tooperate (700 nm for photosystem I and 680 nm for photosystem II)?arrow_forwardThere are two photosystems ( I and II) involved in the light-dependent reactions of photosynthesis. What is the functional difference between these two photosystems?arrow_forward
- n cyclic photophosphorylation in photosystem I, ATP is produced, even though water is not split. Explain how the process takes placearrow_forwardWhy is a hypotonic buffer used for the resuspension? 1.DCPIP passes easily across the intact chloroplast membrane, but can't get into the thylakoid, so electron transport could not be reliably measured if using a hypotonic buffer. 2.To gently lyse the chloroplasts, leaving the electron transport membranes intact, whilst allowing DCPIP access 3.To gently separate the chloroplasts from each other, leaving the electron transport membranes intact, whilst allowing DCPIP access 4.DCPIP cannot easily across the intact chloroplast membrane, so electron transport could not be reliably measured if using a hypotonic buffer.arrow_forwardIt is believed that the ratio of cyclic photophosphorylation to noncyclicphotophosphorylation changes in response to metabolic demands. Ineach of the following situations, would you expect the ratio to increase,decrease, or remain unchanged?(a) Chloroplasts carrying out both the Calvin cycle and the reduction ofnitrite (NO2-) to ammonia (This process does not require ATP.)(b) Chloroplasts carrying out not only the Calvin cycle but also extensiveactive transport(c) Chloroplasts using both the Calvin cycle and the C4 pathwayarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- BiochemistryBiochemistryISBN:9781305577206Author:Reginald H. Garrett, Charles M. GrishamPublisher:Cengage Learning
Biochemistry
Biochemistry
ISBN:9781305577206
Author:Reginald H. Garrett, Charles M. Grisham
Publisher:Cengage Learning